Vortex-induced vibration of a slender single-span cylinder

N. Oikou
Delft University of Technology, the Netherlands

The goal of this paper is to study the vortex-induced vibration of slender cylindrical structures. For this purpose, a 2D model that calculates the coupled cross-flow and in-line vibrations of a flexible single span beam is developed. A wake oscillator known to match well with free vibration experiments on rigid elastically mounted cylinders is employed for the description of the vortex forces acting on the pipe. The frequency of the oscillating beam is determined from the Fourier spectrum of the analysed time series and is presented, together with the maximum oscillating amplitudes over a range of flow velocities. The model is compared with measurements from experiments and good agreement is found.

Key words: Vortex-induced vibration, non-linear dynamics, wake oscillator, fluid-structure interaction, floating pipeline